2V - L
ACRONYMS AND DEFINITIONSNOTE: This Acronyms and Definitions listing contains technical terms applicable to Ford Motor Company products. It is not intended to be an all-inclusive dictionary of components and their functions. If a detailed description of a particular system or component is desired, refer to the applicable Vehicle System for the specific vehicle being serviced.
2V: Two Valve engine configuration.
4V: Four Valve engine configuration.
ABS: Anti-lock Brake System.
A/C: Air Conditioning. A vehicle accessory system that modifies the passenger compartment air by cooling and dehydrating the air.
ACC: Air Conditioning Clutch. Indicates status of the A/C clutch.
ACCS: Air Conditioning Cycling Switch. Indicates status of the A/C cycling switch.
ACD: Air Conditioning Demand. A signal input to the PCM from the Air Conditioning control panel.
ACP: Air Conditioning Head Pressure or A/C cycling switch input state.
ACPSW: Air Conditioning Pressure Switch.
ACPV: Air Conditioning Head Pressure Volts. A voltage input to the Powertrain Control Module (PCM) from the ACP switch or sensor.
ACR: Air Conditioning Relay. Commanded output controlled by the PCM and acts as an A/C cutout control during heavy acceleration.
A/D: Analog-to-Digital. Analog-to-Digital signal conversion.
ADC: See ATDC.
AFCM: Alternative Fuel Control Module.
AIR: Secondary Air Injection.
AIRB: Secondary Air Injection Bypass.
Air Diverter: Air Diverter Valve. Part of the EAIR system. Diverts fresh air to the exhaust system when the electric air pump is commanded on.
AIR EVAL: Air System Evaluated. Displays a YES or NO status indicating whether the Air System has been evaluated for OBD (On-Board Diagnostic) II purposes.
Air/Fuel Ratio: Air to fuel mixture ratio. An air/fuel mixture that is 14.7:1 is also called stoichiometry.
AIRM: Secondary AIR pump monitor.
Ambient Air Temperature: Temperature of the air surrounding an object.
Analog (Electrical/Electronic): An electrical signal that can obtain any value within the voltage limits of the signal.
ARB: Air Resource Board.
ARPMIDES: Ancillary RPM Desired. RPM required to maintain the vehicle speed commanded by Speed Control Command Switch (SCCS) inputs.
ASCII: American Standard Code for Information Interchange.
ATDC: After Top Dead Center. The location of the piston after it has reached the top of its stroke. Measured in degrees of crankshaft rotation.
AVOM: Analog Volt-Ohm Multimeter. Readings are indicated by a sweep hand on a printed scale, rather than a digital display.
AWD: All-Wheel Drive.
BARO: Barometric Pressure.
Base Idle: Idle rpm determined by the throttle lever hardset on the throttle body with the IAC solenoid disconnected.
Base Timing: Spark advance in degrees before top dead center of the base engine without any control from the PCM or ICM.
Battery Positive Voltage (B+): The positive (+) voltage from the battery or any circuit connected directly to the battery. Compare "Vehicle Power (VPWR)."
BAT TEMP: Battery Temperature.
BJB: Battery Junction Box.
BOB: Breakout Box. A test device which connects in series to the PCM and PCM harness.
BPA: Brake Pedal Applied switch. Typically located on the braking system master cylinder. Can be hydraulic or electric.
BPP: Brake Pedal Position. Indicates the position of the brake pedal, based on input from the Brake Pedal Position (BPP) switch.
BRAKE LMP or BRKL: Brake Warning Lamp Status. Activates the Brake Warning Lamp by applying voltage to the control line.
BTDC: Before Top Dead Center. The location of the piston before it has reached the top of its stroke. Measured in degrees of crankshaft rotation.
Bus + or Bus -: Multiplex circuits that carry Standard Corporate Protocol (SCP) data from module to module and to the DLC.
CAC: Charge Air Cooler. Formerly known as Intercooler. A device which lowers the temperature of pressurized intake air.
CAFE: Corporate Average Fuel Economy. A set of federal requirements and regulations which govern fuel economy standards.
CANVNT: Canister Vent Solenoid.
Catalyst: Catalytic converter. An in-line exhaust system device used to reduce the level of engine exhaust emissions.
CAT EVAL: Catalyst System Evaluated. This item indicates YES when the Catalyst Efficiency Monitor has successfully completed.
CCM: Comprehensive Component Monitor.
CCRM: Constant Control Relay Module. A relay module that provides ON-OFF control of various EEC components.
CD A through J: Coil Driver 1 through 10.
Centralized Testing Facility: State government operation. Provides Inspection/Maintenance (IM) and safety inspections.
CGND or CSE GND: Case Ground. Provides a ground source for the PCM or ECU case.
CHT: Cylinder Head Temperature. Units are displayed in either degrees Fahrenheit or Centigrade.
CHTIL: Cylinder Head Temperature Indicator Lamp.
CHTV: Cylinder Head Temperature Voltage. The actual voltage drop across the CHT sensor thermistor.
CID: Cylinder Identification. PCM input signal from Camshaft Position Sensor.
CKP: Crankshaft Position. Senses the position of the crankshaft.
CKP+, CKP-: CKP+ is the Crankshaft Position (CKP) sensor signal wire. CKP - is the signal return.
CL: Closed Loop. An operating condition or mode which enables operation based on sensor feedback.
CMP: Camshaft Position. Indicates camshaft position.
CMPFM: Camshaft Position Failure Mode. Indicates when the PCM identifies a CID/CMP fault.
CMS: Catalyst Monitor Sensor. Downstream H025.
CMVSS: Canadian Motor Vehicle Safety Standards.
CNG: Compressed Natural Gas.
CO: Carbon Monoxide. A colorless, odorless and toxic gas that is a component of auto exhaust emissions.
CO(2): Carbon Dioxide. A colorless, odorless gas that is a normal by-product of the combustion of fuel.
Coil: A device consisting of windings around an iron core. In a spark ignition system, designed to increase voltage.
Cold Soak: Time given to a vehicle to sit at a low temperature (typically below 68°F / 20°C) until the temperature of external and internal components stabilize.
CONT: Continuous Memory. The portion of KAM (Keep Alive Memory) used to store DTCs generated during Continuous Memory Self-Test.
Continuous Memory Self- Test: A continuous test of the EEC system conducted by the PCM whenever the vehicle is operating.
CPP: Clutch Pedal Position. Indicates clutch pedal position.
CPP Switch: Clutch Pedal Position Switch. Located on the clutch pedal and detects when the clutch pedal is depressed.
CQIS: Common Quality Indicator System.
CSE GND: Case Ground.
CT: Closed Throttle Mode. A mode when the PCM varies the pulse width of the fuel injectors to obtain the air/fuel mixture appropriate for closed throttle operation.
CTO: Clean Tach Output. Signal used to drive the instrument panel tachometer.
Data Communications Link: A communication path between various in-vehicle electronic modules. Accessed by scan tools through the Data Link Connector (DLC).
DC: 1. Direct Current. Electric current flowing in one direction. 2. Duty Cycle. The voltage measurement of ON time versus the full cycle period, expressed in percent.
DCL: Data Communication Link.
DI: Distributor Ignition. A system in which the ignition coil secondary circuit is sequenced by a distributor.
Digital: Controls process information by switching the current or voltage ON and OFF.
DLC: Data Link Connector. J1962 connector providing access to vehicle diagnostic information.
DOHC: Dual Overhead Cam. An engine configuration that uses two camshafts positioned above the valves.
DOL: Data Output Line. A circuit that sends certain information from the PCM to the instrument cluster.
DPFEGR: Differential Pressure Feedback Exhaust Gas Recirculation. System that uses a pressure transducer to control the operation of the Exhaust Gas Recirculation (EGR) Vacuum Regulator Valve.
DRI: Deposit Resistant Injector. A fuel injector designed to prevent build-up of carbon and other unwanted deposits.
DRL: Daytime Running Lamps. A system that keeps the vehicle running lamps on at all times while the vehicle is operating.
DTM: Diagnostic Test Mode. A level of capability in an On-Board Diagnostic (OBD) system.
DTC: Diagnostic Trouble Code. An alpha/numeric identifier for a fault condition identified by the On-Board Diagnostic System.
DVOM: Digital Volt-Ohm Meter.
E-85: Fuel containing 85% ethanol alcohol.
EAIR: Electric Secondary Air Injection. A pump-driven system for providing secondary air using an electric air pump.
EAIRM: Electric Secondary Air Pump circuit Monitor.
ECT: Engine Coolant Temperature. Displayed in either Fahrenheit or Centigrade.
ECTV: Engine Coolant Temperature Voltage. The actual voltage drop across the ECT sensor thermistor.
ECU: Electronic Control Unit. A module that handles the control strategy and monitors system inputs or outputs.
EEC: Electronic Engine Control system.
EEC-V: Fifth generation EEC system.
EFT: Engine Fuel Temperature.
EFTA: Bank 1 input. EFTA is displayed in either Fahrenheit or Centigrade.
EFTAV: Voltage drop across the EFTA (Bank 1) sensor thermistor.
EFTB: Bank 2 input. EFTB is displayed in either Fahrenheit or Centigrade.
EFTBV: Voltage drop across the EFTB (Bank 2) sensor thermistor.
EGR: Exhaust Gas Recirculation. A process in which a small amount of exhaust gas is routed into the combustion chamber.
EGR EVAL: Exhaust Gas Recirculation System Evaluated. EGR EVAL will display YES when the monitor is complete.
EGRMDSD: Electric Exhaust Gas Recirculation Motor Desired position. The PID name used to operate the Electric Exhaust Gas Recirculation (EEGR) valve with scan tool's output state control.
EGRS: EGR Shutoff. A normally closed solenoid that applies vacuum to the EGR valve when energized by the PCM.
EGRT: Exhaust Gas Recirculation Valve Temperature Sensor. A temperature sensor that is threaded into the bottom of the intake plenum.
EGR Vacuum Regulator: Controls vacuum to the EGR valve by a duty cycle signal from the PCM.
EGRVR: Exhaust Gas Recirculation Vacuum Regulator. Solenoid which varies the vacuum to the EGR valve by varying the duty cycle to the regulator.
EGRVRA: Exhaust Gas Recirculation Vacuum Regulator Actual (volt). The actual state of the commanded output.
EGRVRF: Exhaust Gas Recirculation Vacuum Regulator Fault. Represents whether a fault exists in the EGRV circuit.
EI: Integrated Electronic Ignition. An Electronic Ignition system that has the Ignition Control Module (ICM) integrated into the PCM.
EI-HDR: Electronic Ignition, High Data Rate. Formerly known as Electronic Distributorless Ignition System.
EI-LDR: Electronic Ignition, Low Data Rate. Formerly known as Distributorless Ignition System.
EMI: Electromagnetic Interference. Usually caused by ignition voltage spikes, solenoids, relay operation or noisy generator contacts.
EOL: End Of Line. A system designed specifically for use at assembly plants to make sure all new vehicles perform to design specifications.
EPA: Environmental Protection Agency (U.S. Government).
EPROM: Erasable Programmable Read-Only Memory. An electronic component in the PCM that requires the electronic storage of information.
ESOF: Electronic Shift-on-the-Fly.
EVAP: Evaporative Emissions. A system to prevent fuel vapor from escaping into the atmosphere.
EVAPCP: Evaporative Canister Purge Solenoid. Controls a solenoid which allows venting of the evaporative purge canister.
EVAPCPF: Evaporative Canister Purge Solenoid Fault. Identifies whether an electrical fault exists for the current commanded state.
EVAPCV: Evaporative Canister Vent Solenoid. Controls a solenoid which seals the EVAP system canister from atmospheric pressure during the EVAP OBD II Monitor test.
Evaporative Emissions Canister: An evaporative emission canister, containing activated charcoal which absorbs and holds fuel vapors.
EVAPPDC: Evaporative Canister Purge Duty Cycle. The duty cycle commanded to the Evap Canister Purge Solenoid by the PCM.
EVO: Electronic Variable Orifice.
EWP: Electric Water Pump.
Exciter Ring: A toothed or notched iron or steel disk, which is the moveable part of a wheel speed sensor.
FAN: Fan Speed. Used in conjunction with vehicles having multiple fan speed control. Displays OFF, LOW, or HIGH status.
FC: Fan Control.
FCS: Fuel Control Solenoid.
FCIL: Fuel Cap Off Indicator Lamp. Indicates that the fuel filler cap was not properly installed.
FEAD: Front End Accessory Drive.
FEPS: Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Programming Signal. 18 volt DC signal sent by the scan tool to initiate PCM reprogramming.
FF: 1. Flexible Fuel. A system capable of using a variety of fuels for vehicle operation. 2. A PID that displays the % alcohol content in fuel.
FFLRN: Flex Fuel Learned. Displays when the PCM's Flex Fuel strategy has completed calculating the inferred alcohol content of fuel.
FFFM: Flexible Fuel Failure Mode. Indicates whether the current Flex Fuel Sensor reading (FF) is reliable or not. Displays a YES or NO.
FFTEMP: Flexible Fuel Sensor - Temperature. Alcohol concentration derived from the signal pulse width.
FFV: Flexible Fuel Vehicle.
FIFO: First In First Out.
FILO: First In Last Out.
FIM: Fuel Indicator Module.
FLI: Fuel Level Input. Used by the Evap monitor to calculate fuel tank vapor volume. Displayed as a percentage.
FLIV: Fuel Level Input Voltage.
FMEM: Failure Mode Effects Management. Operating strategy that maintains limited vehicle function in the event of a PCM or EEC component failure.
FP:1. Fuel Pump. Indicates whether the pump has been commanded ON or OFF by the PCM. 2. Fuel Pump (Modulated). Fuel pump duty cycle percentage.
FPDM: Fuel Pump Driver Module. A module that controls the electric fuel pump.
FPF: Fuel Pump Fault. Identifies whether a fault exists in the FP circuit.
FPM: Fuel Pump Monitor. Monitors the Fuel Pump I circuits for faults.
Freeze Frame: A block of memory containing the vehicle operating conditions at a specific time.
FRP: Fuel Rail Pressure. Based on FRP V.
FRP V: Fuel Rail Pressure Voltage. A voltage input to the PCM from the Fuel Rail Pressure Sensor.
FSC: Fail-Safe Cooling.
FSV: Fuel Shut-off Valve. A component of Natural Gas Vehicles. This valve either allows or prevents Natural Gas flow to the fuel rail.
FSVF: Fuel Shut-Off Valve Fault. Indicates if there is a fault in the FSV circuit. Displayed as YES or NO.
FSVM: Fuel Shut-off Valve Monitor. Monitors operation of the Fuel Shut-Off Valve / circuit.
FTP: Fuel Tank Pressure. Displayed as inches of water, kPa, or volts.
FTP V: Fuel Tank Pressure Voltage. From the FTP transducer.
FUEL PR: Fuel Pressure. Measurement of the force of the fuel delivered via the fuel pump.
FUELPW: Fuel Pulse Width. Displays the commanded pulse width at time of last data update.
FUELPW1: Fuel Injector Pulse Width #1. Corresponds to injectors normally affected by O2S1 (HEGO1).
FUELPW2: Fuel Injector Pulse Width #2. Corresponds to injectors normally affected by O2S2 (HEGO2).
FUELSYS: Fuel System Status (OPEN/CLOSED Loop). Formerly known as LOOP.
Fuel Tank Vapor Valve: A valve mounted in the top of the fuel tank that vents excess vapor and pressure from the fuel tank into the Evaporative Emission Control System.
FWD: Front Wheel Drive.
GEM: Generic Electronic Module.
GEN: Generator.
GENF: Generator Output Fault.
GENFDC: Generator Field Control Output.
GFS: Generator field signal monitor.
GND: Ground.
GPM: Grams Per Mile. Also known as Gallons Per Minute.
GPS: Global Positioning Satellite.
Green State Vehicle: Formally known as California Emissions. A vehicle that is equipped with California on-board diagnostics.
GSS: Gear Select Solenoid.
GVW: Gross Vehicle Weight.
Hall Effect: A process where current is passed through a small slice of semi-conductor material and a magnetic field to produce a small voltage in the semi-conductor.
Hard Fault: A fault currently present in the system.
HC: 1. Hydrocarbon. A by-product of combustion and a component of auto exhaust emissions. 2. High Compression.
HCF: Hydraulic Cooling Fan.
HCFD: Hydraulic Cooling Fan Drive.
HFC: Hydraulic Cooling Fan.
HFCF: High Fan Control Fault. Identifies if there is a fault in the HFC circuit.
HFP: High Fuel Pump.
HLOS: Hardware Limited Operating Strategy. A mode of operation where the PCM replaces output commands with fixed values in response to internal PCM malfunctions.
HO: High Output.
HO2S: Heated Oxygen Sensor. Formerly known as Heated Exhaust Gas Oxygen (HEGO) Sensor. Provides information on rich or lean exhaust conditions to the PCM.
Hot Soak: Period of time after an engine operates where localized combustion heat dissipates throughout the engine.
HTR, HTR11, HTR12, HTR21 H1R22, HTRX1, HTRX2: HO2S Heater. Heater element for the HO2S sensor.
Hydrogen: Chemical symbol H. Highly flammable gas.
Hz: Hertz. Cycles per second.
IAC: Idle Air Control. Electrical control of throttle bypass air.
IAT: Intake Air Temperature.
IATV: Intake Air Temperature Voltage. Actual voltage drop across the IAT sensor.
IAT2: Intake Air Temperature 2. Displayed in either Fahrenheit or Centigrade. Used on supercharged vehicles.
IAT2V: Intake Air Temperature 2 Voltage. Actual voltage drop across the IATV2 sensor.
IC: Integrated Circuit. A small Semi-Conductor device capable of doing many separate circuit functions.
ICM: Ignition Control Module. The module that controls the ignition system.
IFDM: Integrated Fuel Delivery Module.
IFS: Inertia Fuel Shutoff.
IGN GND: Ignition Ground.
Ignition: System used to provide high voltage spark for internal combustion engines.
IGNKEY(IGKY): Ignition Key status.
IGNSW (IGSW): Ignition Switch Position.
IMRC: Intake Manifold Runner Control. Controls airflow through the high-speed runners in the intake manifold.
IMRCM: Intake Manifold Runner Control Monitor. Monitors the IMRC / circuits for faults.
IMTV: Intake Manifold Tuning Valve. Controls airflow through runners in a split intake manifold.
INJ1, INJ2, INJ3, INJ4, INJ5, INJ6, INJ7, INJ8, INJ9, INJ1O: lnjector number or its signal output from the PCM.
Injector: A device for delivering metered pressurized fuel to the intake system or the cylinders.
Intake Air: Air drawn through a filter and distributed to each cylinder for use in combustion.
Intercooler: See CAC.
IPATS: Integrated Passive Anti-Theft System.
ISO: international Standards Organization.
KAM: Keep Alive Memory. A portion of the memory within the PCM that must have power even when the vehicle is not operating.
KAPWR: Keep Alive Power. Dedicated, unswitched power circuit that maintains KAM.
Key On Engine Off Self- Test: A test of the EEC system conducted by the PCM with power applied and the engine at rest.
Key On Engine Running Self- Test: A test of the EEC system conducted by the PCM with the engine running and the vehicle at rest.
KEYPWR: Key Power. Battery voltage supplied when the ignition key is in the ON position.
Knock: The sharp metallic sound produced when two combustion pressure fronts collide in the combustion chamber of an engine.
KOEC: Key On Engine Continuous.
KOEO: Key On Engine off.
KOER: Key On Engine Running.
KPA: Kilopascal. Unit of pressure. 3.386 kPa = 1 inch of mercury (Hg.).
KPH: Kilometers Per Hour.
KS: Knock Sensor. Detects engine knock.
L: Liters. The unit of volume in the metric measuring system. One liter equals 1.06 quarts.
LEV: Low Emissions Vehicle.
LFC: Low Fan Control.
LFP: Low Fuel Pump. Reduced operating speed for multi-speed fuel pumps.
LIFO: Last In First Out.
LILO: Last In Last Out.
LONGFT1, LONGFT2: Long-Term Fuel Trim. Fuel flow adjustment determined by the PCM.
LOOP: indicates OPEN or CLOSED loop status.
LPG: Liquefied Petroleum Gas.
LPLR: Low Pressure Low Resistance fuel injector.